Ok, pet peeve time. I promise I won’t do this too often. This will be short and sweet.
Lag is entirely network related. Most likely all causes of lag are outside of your direct control.
Frame rate is entirely hardware related. Most likely all causes of poor frame rate are within your direct control.
If you get long pauses in gameplay and then everything catches up, that’s lag. The latency between yourself and the server is too high, and information is taking too long to get from one to the other, so the game may “re-sync” everything and you suddenly find yourself in a situation you were not in a mere second earlier. Rubberbanding (where your character snaps back to a position they were a second before) is also related to this. If your frame rate drops when there are too many FX on the screen, that -might- be lag, but it most likely is a frame rate issue. I say “might” because all those FX are coming along with the data packets of what those FX are doing in the game, and losing one or several of those may cause your game to hiccup in such a way that it simulates poor frame rate.
If your frame rate drops when you turn on a graphic effect like shadows, anti-aliasing, or anything else that’s a client-side visual option, then you are likely not seeing lag, but seeing a frame rate “hit” because your hardware isn’t up to the task asked of it. If you have a rock solid frame rate and you go to a busy area with a lot of characters and a high level of graphic detail, and your frame rate drops, that’s not lag, that’s you asking your video card, processor, and memory to do more than it is designed for and thus instead of serving you 60 frames of graphical goodness every single second, it has to work harder and only deliver you 20 frames per second. (Note: with all the characters milling about in the above scenario there may be some lag sneaking in as well, as you are getting constantly updated on their position).
So how do you fix it when you have lag or poor frame rate? Well, there are two different answers, depending on which you have.
Lag may be entirely out of your direct control. It has a lot to do with internet routing and the speed of your internet service, how many people are sharing said service, how well the service is run, etc. If you use a cable modem, getting a higher bandwidth connection may help with lag you are experiencing, making sure your DOCSIS on your cable modem is the one recommended by your provider, or simply having a tech come out and make sure your “lines” are “clean” coming into the house. I know that for my cable modem at home, we had too many “splitters” before the cable in from the street arrived at our cable modem, and that caused all sorts of headaches. The tech put in one splitter at the street, ran a brand new cable directly into the modem, and things have been great ever since.
Frame rate is within your control, only you probably won’t be happy with the steps you need to take. First is to reduce the graphic levels of whatever it is you are playing until you get a consistent FR that you like. What you may not like is what your game looks like at this point. In this case the solution is one you need to throw money at. Hopefully a new video card from NVidia or ATI is all you need to solve your problem, but always check the specs. Video cards range in price from $50 to $500, and most of the time you get what you pay for. Many $50 cards today used to be $500 cards about 3 or 4 years ago. If this level of card is all you need to solve your frame rate issues, that’s great. However, your poor FR is most likely because you have a brand new game and you want it to look like the screenshots on the box. In that case, you are looking closer to the $500 cards.
Always be wary of buying a bleeding edge card if you are not building a system around it. Power usage, card size, and motherboard/CPU are all things you need to take into account. If your power supply can’t bring the juice, you won’t even be able to boot your system with that card in it. If the card is literally too big to fit in your case, you will be a sad panda. And if your motherboard/CPU are woefully out of date it won’t matter how awesome that card is, you are still limited and will need to upgrade that part of your computer as well.
Now in closing, I don’t expect to win in my crusade to get people to say what they mean when it comes to the visual performance they are seeing, but if this article educated just ONE person in the difference and they stop using the word “lag” to mean a problem with their video hardware, then I can sleep a little easier.